1. Field of the Invention
The present invention relates generally to the field of separating particles of precious metals. More specifically, the present invention discloses a continuous cycle apparatus for separating precious metals from concentrate.
2. Statement of the Problem
Placer mining operations present a number of unique problems in separating gold particles from common materials. At the small end of the scale, many of these same difficulties also arise in gold panning operations. Namely, these types of mining operations produce relatively small quantities of concentrate that must then be further processed to separate out the particles of gold or other precious metals contained therein. In many cases, these gold particles are so minute that conventional separation devices are less than completely effective in recovering the available metal values.
Another problem arises from the small scale of many placer mining operations. This makes large capital expenditures for equipment difficult to justify from an economic point of view. Therefore, separation equipment for use in small mining facilities must be relatively inexpensive to purchase repair, and operate. Finally, many mining operations are located in remote and rugged locations. This dictates that separation equipment should be compact, easy to transport, and suitable for use in hostile environmental conditions.
A number of systems for separating precious metals from common materials have been invented in the past, including the following:
______________________________________ Inventor Pat. No. Issue Date ______________________________________ Hibbard 4,319,985 Mar. 16, 1982 McCann 4,525,270 June 25, 1985 Kaufman 4,642,180 Feb. 10, 1987 Balkus 4,826,251 May 2, 1989 Brosseuk 5,108,584 Apr. 28, 1992 ______________________________________
Hibbard discloses a gold concentrator having a housing at the end of a sluice into which a quantity of sand, rock and gold particles is deposited. A hose delivers water under pressure to create a suspension of particles and water in the housing. The suspension flows downwardly into a series of sluices which trap the gold particles.
McCann discloses a system for separating heavy minerals, such as gold, silver, and the like, from common material by applying water to the mixture of materials and allowing their different specific gravities to separate them in a sluice holding a riffle mat. A pump 17 recirculates water from a reservoir back into the feed hopper 38. A portion of the flow 21 is directed upward from the bottom of the feed hopper. Another portion of the flow is directed through apertures 23 in the hopper's walls. The resulting slurry flows out through apertures in the bottom of the hopper to enter the sluice.
Kaufman discloses a portable apparatus for recovery of placer gold. The apparatus includes an inclined riffle board containing holes through which jet of air flow to separate gold particles from pulverized ore, sand, debris, and the like. An attached bellows provides the required air flow.
Balkus discloses a dredging platform having a water pump that creates suction in a hose for drawing loose materials from the bottom of a stream into the hose for transport to a sluice and vibratory screen.
Brosseuk discloses an apparatus for extracting heavy metals from ore having a perforated inner drum and a rotating, inclined outer drum with a spiral vane extending the length of its inner surface. A spray of water is directed onto ore contained in the inner drum. A sluice box receives the slurry of water and ore particles discharged from the upper end of the outer drum.
3. Solution to the Problem
None of the prior art references uncovered in the search show a continuous cycle apparatus for separating gold particles having the structure of the present invention. In particular, the unique funnel-shaped hopper (and metering rod) of the present system provide an effective and efficient means for separating gold particles from concentrate. In addition, the present system is inexpensive to build and maintain, and can be easily transported for use in remote locations.